The Salmonella Poona outbreak that started last year in cucumbers imported from Mexico caused 907 known illnesses in 40 states, sent at least 204 people to the hospital, and caused four known deaths. The Centers for Disease Control and Prevention has finally declared the outbreak to be over, concluding that they couldn’t find how the cucumbers became contaminated in the first place.

Two companies, Custom Produce Sales and Andrew & Williamson, were linked to the outbreak and recalled batches of cucumbers, though the CDC was only able to definitively link the Andrew & Williamson cucumbers to confirmed cases.

The most recent known illness was on February 29, 2016. The CDC notes that cucumbers that were part of the affected batches shouldn’t have still been available, but illnesses may have been due to cross-contamination.

Authorities were able to identify the source of Salmonella by interviewing patients, and comparing their recollections of what they had eaten recently to similar interviews of people who didn’t have Salmonella. While 75% of the people who were sick remembered eating cucumbers, only 47% of the healthy people remembered eating cucumbers recently.

The deaths associated with this outbreak all happened in the southwestern United States, but authorities say that two of the three people who were infected in California died from causes other than Salmonella.

Symptoms of illness caused by Salmonella include diarrhea, fever, and abdominal cramps. Serious illness is more likely in people with pre-existing health problems, young children, and the elderly.

Multistate Outbreak of Salmonella Poona Infections Linked to Imported Cucumbers (Final Update) [CDC]

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